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Updated: May 30, 2026
08:12
Measurement of Mitochondrial Respiration in Human and Mouse Skeletal Muscle Fibers by High-Resolution Respirometry
Published on: October 4, 2024
Exercise can induce temporary mitochondrial and contractile dysfunction linked to impaired respiratory chain complex
Maria Schoepe1, Andrea Schrepper, Michael Schwarzer
1Department of Cardiac Surgery, Heart Center Leipzig, University of Leipzig, Germany.
Metabolism: Clinical and Experimental
|August 6, 2011
Summary
High-intensity exercise training can temporarily impair heart function and mitochondrial respiration. This exercise-induced cardiac dysfunction is linked to reduced electron transport chain activity and is intensity-dependent.
Area of Science:
- Cardiovascular Physiology
- Mitochondrial Biology
- Exercise Science
Background:
- Repetitive exercise impacts cardiac physiology.
- Previous research focused on exercise effects solely at the end of training periods.
Purpose of the Study:
- To investigate the impact of two treadmill inclination protocols on cardiac and mitochondrial function during a 10-week training period.
- To assess the temporal effects of exercise intensity on cardiac contractility and mitochondrial respiration.
Main Methods:
- Assessed cardiac function (ejection fraction, wall thickness) and mitochondrial respiration in animal models.
- Analyzed gene expression of myosin heavy chain isoforms and nuclear respiratory factors (NRFs).
- Measured electron transport chain complex activities at 6 and 10 weeks of training.
Main Results:
- 16% incline training induced hypertrophy but caused temporary contractile dysfunction and decreased mitochondrial respiration at 6 weeks.
- Reduced nuclear respiratory factors (NRFs) and electron transport chain complex activities were observed with high-intensity exercise.
- 10% incline training resulted in less hypertrophy and maintained cardiac and mitochondrial function throughout the study.
Conclusions:
- Repetitive, high-intensity exercise can lead to temporary cardiac and mitochondrial dysfunction.
- Impaired respiratory chain complex activity is intensity-related and reversible.
- Exercise intensity is a critical factor in exercise-induced cardiac adaptations and potential dysfunctions.
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